Forced-draft-producing device



-: Sept. 30 1930.

J. W. BRAGSTAD FORCED DRAFT PRODUCING DEVICE Filed Dec. 15, 1929 'lllllllll.

Patented Sept. 30, 193( PATENT.joFFicef 'JosErIrw. BItAesIAn' oF nL HURsr, ILLInoIs FdRCED-DRAFT-PRODUQING DEVICE Application filed December 13; 1929. Serial No. 413,801.

This invention relates to improvements in devices for producing forced drafts, particularly adapted though not necessarily limited in its use, for hot air furnaces, and one of the objects of the invention is to provide improved means for drawingcold air outof a house or room and for forcing warm air thereintop a V I A further object is to provide improved means forfiltering theair supply tothe fan and improved means wherebywhen the fan is rendered inactive the filter will be automatically adjusted so as not to interfere with or obstruct the natural circulation of air around the fan and to the furnace.

A further'object is to provide improved means including a damper for. cutting of? the free circulation of air when the fan or blast producing-device is active and means responsive to the movement or adjustment of the said damper for controlling the opera tion of the fan or blast creating device.

To the attainment of these ends andthe' accomplishment of other new and useful objects as will appear, the invention consists in the features of novelty inisubstantiallythe construction, combination and arrangementof theseveral parts hereinafter more fully described and claimed and shown in the accompanying drawing illustrating this invention, and in which I Figure 1 is a ,VlBW partly in elevation, partly in vertical section and partly broken away, of a device of this character constructed in accordance with the principlesof this invention, and showing. the same as used in connection witha flue, and with the parts inv position so as to permit a free and natural circulation of air to the furnace. y 7

Figure 2 is a detail sectional view on line 22, Figure l.

Figure 3 is a view similar to Figure 1, showing the parts in a diiferentposition with the damper closed to produce a forced cirtaken culation andthe filter correspondinglyadjusted. j Referring more particularly to the drawingithe numeral 10 designates generally a flue of any desired size and configuration forre ceiving and, conducting cold air away from V a room -or-house. V This flue may (have communication with the room through the floor 11 thereof and by meansof the ordinary =registers or grating 12. r r v I r The fluemay be'of any desired size and configuration and communicatingtherewith and preferably adjacent the top thereof through an opening 13, is an auxiliary flue 14, which latter has communication as at 15 60 with a furnace l6. v

Arranged in an opening in thewall' between the flue 10 and the auxiliary flue 14 is a blast creating device, suchas a fan designated generally by the reference numeral 16, and the fan is preferably arrangediinialinement with the opening 15 leading to the furnace. I I c H Within the flue 10 is a filterbag 18 which is constructed of any desired or suitable mak 7 terialand is held against normally collapsing in any desired or suitable manner.

ley or other dev'ice23 supported by thewall so. of the flueand may pass through suitable guides 24"to a position in proximityqto. an

opening 25 preferablyjadjacent.the base of the-flue and may be anchored as at 26; A:

door27 forms a closurefor the opening2 5 "35;

Arranged preferably adjacent the bottom-i of the opening 13 between the flues is an arm 28 v which, is connected with a; damper orslide, 29, the-latter-being adapted tobe movedfromr the position shown in Figure 1 to thejposi no r Thelow er end of the filter is, open rand-is connected a purpose to be set forth. l/Vhen, however,

the arm 28 reaches the limit of its lowermost movement or even at the limit of its uppermost movement tllGfiltGl 18 may be lowered with respect-to the arm -28'bydetaohing the flexible member 21. i'rom its anchor 26.

A lever 31 is pivotally mountedas at 32 upon a suitable support 'prefera b lyone of the walls of the auxiliary flue and is connected by its other end by ineansof a and slot connection 33-3%l withthe arm28 and serves as a means for raising and lowering lthe'iaam'28 and the damperi29. This may be effected in any suitable manner tprer through th e mediumot-thearm28.

erabl'y by means of pu ll cord lOT'CllElil'Il135 leading to :any suitable point. Thus it will be'seen that when (the pull cord or chain 35 I is drawn upwardly-from the position shown in :Figure -1, the lever -31 will be rocked about its pivot andtthisavill raise oriclose theadampor '29 and" also :raise the arm '28 to also raise or extend the filter l8. p f l Theopening 13 and damper 29 :are :provided for the purpose of permitting a free circulation of air when the "draft or blast creating device is inactive :as it will be ob served that when :the parts are in the position shown in Figure 1, the blast creating device or ztan as inactive and with the parts as shown iniFligure' 1-,'free air will cireulate through th'eigr'atiln'g i12into the flue- 1.0, fout 'of the opening 13, ethrtough the auxiliary zfiue 14 fand iintoflthe-furnace, :At this time it is advisable to drop the filter 138 so that it wil l not interfere with or obstruct such free :circnlation of air aind this is accomplished When, however, it is desired "to produce a forced draft, a nd to *oh'ange the direction of flow o f a-ir,:so that the air instead of flowing through t11e=opening 13 into the iflue ll will flow threugh the filt'er 18,- the lever 31 is rocked *to raise the arm 28 :and :damper 29 to close the op'ening and as the damper 29 is beinfg raisedor c'los'edihearr'n' 28 co-Operati ng with the flexible 'member 21 will move 1 the par'ts into the position shown in Figure 3 and thereby closethe opening 13. In this position 'and when the fan is operating it will be manifest that the air drawn into the flue 10 must pass through the filter '18 before being discharged intothe furnace.

It is advisable that "the damper 29 is open or in the position shown in Figure 1, to shut oii the blast producing device and when the damperf-29 is =cl'osed, to start the blast pro driving-device. This may' be'eflected in any pin suitable manner, preferably through the medium of a switch 36 having an operating handle 37 0f the ordinary type which moves the handle in one direction normally under spring pressure. To this handle 37 is connected a pull cord or chain 33 which is connected as at 39 with the lever 31. Thus when the lever 31 is moved from the position shown in Figure 1 to the position shown in Figure 3, the damper 29 will be closed and the switch 36 will be operated to start the blast producing device 17. \Vhen the damper 129 is opened and the lever 31 moved to the .position shown in Figure 1, the pull. cord or chain 38 willbccome slack and the normal tendency of the switch 36 will cause the lever 37 ,to move in a direction to interrupt the 'circuitto the blast producing device 17 and thereby cause ,t'hesame to stop.

A cord or chain 40 may be provided as a means 41 01 anchoring the portion of "the filter adjacent the blast creating de-vice '17 so as'to prevent the same from being draw-nzinto the blast creating device by the suction tth'ereort.

Whilethe preferred form ofthe invention has been :herein shown and described, it is to be understood that various changes anay be made in the details of construction and in the combination and arrangement of the several parts, within :the :scope of the claims, without departing from the spirit of this invention. a

What is-claimedasine-w is:

-1. In combination aflue,.a tubula1-filter in the flue, an auxiliaryifluefhavingrcommunication with ithe .first said =flue, a damper for closing :said communication between the fluesymeans whereby-the movement of the damper to open said V communication will move the filter into-a positionout ofthe way with respect tosaid communicating opening to allow the air free access .tosaid opening, means for controlling the movement of the damper at will, .andmeansfior inducing circulation of air through .saidffilter when the said damper is closed.

"2. In combination a flue, a tubular filter in the flue, an auxiliary flue having communication with the first said *flue, a "damper for closing said communication between the flues, means whereby the movement of the damper to open said communication will move the filter into a position outof the way with respect ito said communicating opening'to allow the air free access to said opening,"1neans for controlling the movement of the damper at will, means for inducing circulation oi air through the filter'whcn the damper is "c'losed,'and means responsive to the movement of'the damper "for controlling the operation of the said circulation inducing means.

3. In 'combinatiom'a'flue having anontl'et, a tubular filter in the fiue, 'means adjacent said outlet for inducing circulation-of air damper for controlling said communication betwe-enthe flues, means for ad usting the damper, and an operative connection between the damper and 'a portion of the filter whereby the filter will, by the movement of the damper, be positioned out of the way with respect to said communicating opening.

4. In combination, a flue having an outlet, a tubular filter in the flue, means adjacent said outlet for inducing circulation of air through the'fiue and filter and throughsaid outlet, an auxiliary flue having communication through an opening with the first said flue and also provided with an outlet, a

damper for controlling said communication between the flues, means for adjusting the damper, an operative connection between the damper and a portion of the filter whereby the filter will, by the movement of the damper be moved out of the way with respect to said communicating opening to allow the air free access to the opening, and means operating automatically to start and stop the operation of said circulation inducing means'upon the operation of said damper. 1

5. In combination, a fiuehaving an outlet, a tubular filter in the flue, means adjacent said outlet for inducing circulation of air through the flue and filter and through said outlet, an auxiliary flue having communication through an opening with the first said flue and also provided with an outlet, a damper forcontrolling said communication between the flues, means for adjusting the damper,an operative connection between the damper and a portion of the filter whereby the filter will, by the movement of the damper, be moved out of the way ofsaidopening, and means operating automatically to start and stop the operation of said circulation lnducing means upon the operatlon t said damper, all o'fsaid parts being housed within the respective 'flues.

6. In combination a flue having a discharge outlet adjacent one end, a fan adjacent said w outlet for inducing circulation of air through saidflue and through said outlet, anauxiliary c flue having communication with the first said flue at a point remote from said outlet, said auxil ary flue havlng an outlet, a damper '2 i for controlling the communicating opening between the flues for changing the path of circulation of the air, a filter in the first said flue and through which filter the air must pass to flow through the outlet of the first said flue, and means whereby the operation of the damper in one direction will move the filter out of the way with respect to the said communicating opening of the fiues.

7. In combination a flue having a discharge outlet adjacent one end, a fan adjacent said outlet for inducing circulation of air through said flue and throughsaid outlet, an auxiliary flue having communication with the filSb circulationotthe air, a'filter inthe first said flue and through which filter the air must" passto flow throughthe outlet of the first said flue, means whereby the operation of the damper in one direction will move the filter outiot' thepway with respect to the said communicating opening of the flues, and means whereby the operation of said damper will control the operation of the said air circulation inducing means.

8. In combination a flue having an outlet, a tan adjacent said outlet for inducing air circulation, a filterin the flue through which the air must pass to said outlet, an auxiliary flue, a communicating opening between the flues at a point remote from said fan, a damper for controlling said communicating opening, means for adjusting the damper, means whereby the filter will be moved out of the way with respect to the said communicating opening, and means whereby the circulation creating means will be rendered active upon the closing of said damper and inactive upon the-opening of the damper. 9. In combination aflue having a discharge outlet, a fan adjacent said outlet, a filter insaid flue and through which filter air must' ter.

10. In combination two flues having communication with each other at separated points, an outlet from one of the flues, a fan adjacent one of the communicating openings, a filter in the other flue through which air must pass to said fan, a damper for closing the other of said'communicating openings,

the last said opening serving as a passage for air from, the filter containing 'fiue to the 7 other flue without passing through the filter,

and means whereby the adjustment of said damper in one direction will move the filter out of the way with respect to the damper controlled opening to permit free access of the air tosaid opening.

' 11. In combination two flues having communication with each other at separated points, an outlet fromone of the flues, a fan adjacent one of the communicating openings, a filter in the other flue through which air must pass to said fan, a damper for closing the other of said communicating openings, tlielast said opening serving as a passage for air from the filter containing flueto the other flue Without passing through the filter, means whereby the adjustment ofsaid; damper in one direction will move the filter out of the Way with respect to thedamper controlled opening, and means responsive to the. operation: of" the; damper for controlling the operation of the fan; 1 v V In testimony whereoflhave signed my name to this specification on this 6th day of December, A. D. 1929. JOSEPH WQBRAGS TAD. 

